Study on the Reaction of Acetone Cyanohydrin with 3,5-Dimethyl-N-α,β-unsaturated Acyl Pyrazole

Guannian Fang, Jun You, Yanchao Yu, Junkai Jing, Bo Liu, Wenju Wu
2020 Youji huaxue  
Cyano compounds are a class of organic compounds with great value. Two different kinds of reactions have been reported using acetone cyanohydrin as reagent and substituted 3,5-dimethyl-N-α,β-unsaturated acyl pyrazole as substrate. The reaction pathway depends on the basic catalysts used when aromatic substituted 3,5-dimethyl-N-α,β-unsaturated acyl pyrazole was used as the substrate. Michael addition reaction occurred in the presence of MgBu 2 with the product yield up to 95%, while alcoholysis
more » ... while alcoholysis reaction of amide occurred in the presence of 1,1,3,3-tetramethylguanidine (TMG), producing β-substituted phenyl cyanoacrylates with 84% yield. However, fatty substituted 3, 5-dimethyl-N-α,β-unsaturated acyl pyrazole and acetone cyanohydrin underwent Michael addition reaction in the presence of MgBu 2 or TMG, the product yield was up to 99%. The possible reaction mechanism when using different basic catalysts was discussed.
doi:10.6023/cjoc202003047 fatcat:mldmfb6nznhklfuozedix5lva4